A grandfather who was among three killed in a triple-car crash west of the Sunshine Coast last weekend was a "good Samaritan" who stopped to pick up a stranger in distress, police said.

Rafferty Rolfe, 25, is due to face Maroochydore Magistrates Court today after he was charged with three counts of murder over the horror crash.

The deadly collision occurred at Federal on the Bruce Highway early last Friday.

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Detective Superintendent Ben Fadian said that at about 3.30am that day, 65-year-old Terry Bishop stopped to pick up 25-year-old Gypsy Satterley from the side of the road.

"He's doing the right thing, picking up a person who's in distress on the side of the road." Fadian said.

Bishop was travelling south from Mackay for a wedding.

After he picked up Satterley, police allege, they were pursued south by a stolen white Isuzu.

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The Isuzu allgedly rammed Bishop's car, spinning it around. He subsequently started driving north on the southbound lanes of the Bruce Highway.

With the Isuzu allegedly still in pursuit, Bishop collided with a car driven by alpaca farmer Jessica Townley, 38.

Bishop, Satterley, and Townley were all killed.

Police said Rolfe, who suffered a head injury in the collision, had been found in the vicinity of the Isuzu.

It's believed Satterley had got out of the Isuzu shortly before Bishop picked her up.

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Superintendent Fadian said Satterley and Rolfe were believed to have had a relationship for several weeks prior to the crash.

There had been no reported incidents between the pair.

Fadian confirmed the murder charge related to Satterley's death was a domestic violence charge.

Police have also charged Rolfe with stealing the Isuzu at knifepoint in Gympie at 4.30pm the day before the crash.

They are still trying to piece together the car's movements between then and the crash and have called on anybody who may have seen it to come forward.

Fadian said police had spoken to a number of people who knew Rolfe and Satterley but others had been "reluctant".

"These people don't usually speak to the police," he said.

"They live on the fringe of society."

Rolfe is still receiving treatment in hospital, Fadian confirmed.

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